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Schistosoma mansoni: tail loss in relation to permeability changes during cercaria–schistosomulum transformation

Published online by Cambridge University Press:  06 April 2009

R. E. Howells ,
S. E. Gerken ,
F. J. Pinto-Ramalho ,
U. Kawazoe ,
G. Gazzinelli  and
J. Pellegrino
R. E. Howells
Affiliation:
Departments of Zoology–Parasitology, Biochemistry–Immunology and Schistosomiasis Research Unit, Federal University of Minas Gerais, 3000 Belo Horizonte, Brazil
S. E. Gerken
Affiliation:
Departments of Zoology–Parasitology, Biochemistry–Immunology and Schistosomiasis Research Unit, Federal University of Minas Gerais, 3000 Belo Horizonte, Brazil
F. J. Pinto-Ramalho
Affiliation:
Departments of Zoology–Parasitology, Biochemistry–Immunology and Schistosomiasis Research Unit, Federal University of Minas Gerais, 3000 Belo Horizonte, Brazil
U. Kawazoe
Affiliation:
Departments of Zoology–Parasitology, Biochemistry–Immunology and Schistosomiasis Research Unit, Federal University of Minas Gerais, 3000 Belo Horizonte, Brazil
G. Gazzinelli
Affiliation:
Departments of Zoology–Parasitology, Biochemistry–Immunology and Schistosomiasis Research Unit, Federal University of Minas Gerais, 3000 Belo Horizonte, Brazil
J. Pellegrino
Affiliation:
Departments of Zoology–Parasitology, Biochemistry–Immunology and Schistosomiasis Research Unit, Federal University of Minas Gerais, 3000 Belo Horizonte, Brazil
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Extract

The hind-body region of Schistosoma mansoni cercariae observed in the scanning electron microscope demonstrates various stages of contraction which may be compared with those of living larvae which are secreting the acetabular gland contents.

No evidence for an extensive lesion was found in cercarial bodies which had shed their tails under experimental conditions. Experiments on the permeability of the larvae to sodium fluoride, methylene blue and amino acids demonstrated that tail loss significantly affects the permeability of the bodies although the effect is greater immediately after decaudation than at later times. Subsequent increases in permeability may be correlated with a change in the general body surface.

Type
Research Article
Information
Parasitology , Volume 71 , Issue 1 , August 1975 , pp. 9 - 18
Copyright
Copyright © Cambridge University Press 1975

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References

Gordon, R. M. & Griffiths, R. B. (1951). Observations on the means by which the cercariae of Schistosoma mansoni penetrate mammalian skin, together with an account of certain morphological changes observed in the newly penetrated larvae. Annals of Tropical Medicine and Parasitology 45, 227–43.Google Scholar
Hockley, D. J. (1968). Scanning electron-microscopy of Schistosoma mansoni. The Journal of Parasitology 54, 1241–3.CrossRefGoogle ScholarPubMed
Howells, R. E., Ramalho-Pinto, F. J., Gazznelli, G., Oliveira, C. C., FiGueiredo, E. A. & Pellegrino, J. (1974). Schistosoma mansoni: the mechanism of cercarial tail-loss and its significance to host penetration. Experimental Parasitology (in the Press).CrossRefGoogle ScholarPubMed
Morris, J. P. (1971). The fine structure of the tegument and associated structures of the cercaria of Schistosoma mansoni. Zeitschrift für Parasitenkunde 36, 15.CrossRefGoogle ScholarPubMed
Race, G. J., Martin, J. H., Moore, D. V. & Larsh, J. E. Jr (1971). Scanning and transmission electron microscopy of Schistosoma mansoni eggs, cercariae and adults. The American Journal of Tropical Medicine and Hygiene 20, 914–24.CrossRefGoogle ScholarPubMed
Ramalho-Pinto, F. J., Gazzinelli, G., Howells, F. E., Mota-Santos, T. A., Figueiredo, E. A. & Pellegrino, J. (1974). Schistosoma mansoni: a defined system for the step wise transformation of the cercariae to schistosomule in vitro. Experimental Parasitology (in the Press).CrossRefGoogle Scholar
Smith, J. H., Reynolds, E. S. & Lichtenberg, F. Von. (1969). The integument of Schistosoma mansoni. The American Journal of Tropical Medicine and Hygiene 18, 28–49.Google Scholar
Stirewalt, M. A. (1963). Cercariae vs. Schistosomula (Schistosoma mansoni). Absence of the pericercarial envelope in vivo and the early physiological and histological metamorphosis of the parasite. Experimental Parasitology 13, 395–406.CrossRefGoogle Scholar